Offset calender rolls

ABSTRACT

Stabilizing mounting for calender rolls, compensating for horizontal deflection of the rolls by offsetting the roll axes horizontally. Stabilizing of the rolls is attained by mounting the lift arms of the rolls on vertically extending swing arms on individual pivots extending transversely of the lift arms. Each swing arm is pivoted to a pivot bracket for the roll at one end, pivotally supports the lift arm intermediate its ends, and is adjustably connected to the pivot bracket at its opposite end by an eccentric pin, movable in an open slot in the swing arm to offset the roll axis as required and to accommodate the insertion of a feeler gage, to determine the direction of the resultant horizontal forces, as the eccentric pin is adjustably moved.

United States Patent [72] Inventor Donald B. De Noyer BeloiLWis. [21] AppLNo 844,962 [22] Filed .Iuly25,1969 [45] Patented Aug.10,1971 [73] Assignee BeloitCorporation BeloiLWis.

[54] OFFSET CALENDER ROLLS 10 Claims, 3 Drawing Figs.

[52] U.S.Cl 100/163, 100/170 [51] lnt.(l B30b3/00 [501 FieldolSearch 100/47, 168,169,170,171,161,162,163,164,165,166

[56] References Cited UNITED STATES PATENTS 2,310,262 2/1943 Shields 100/168X 3,044,392 7/1962 Minarik 100/162 3,066,876 12/1962 Verdier 100/161X 3,158,088 11/1964 Seidel 100/163 Primary Examiner-Billy .1. Wilhite AttorneyHill, Sherman, Meroni, Gross & Simpson ABSTRACT: Stabilizing mounting for calender rolls, compensating for horizontal deflection of the rolls by ofi'setting the roll axes horizontally. Stabilizing of the rolls is attained by mounting the lift arms of the rolls on vertically extending swing arms on individual pivots extending transversely of the lift anns. Each swing arm is pivoted to a pivot bracket for the roll at one end, pivotally supports the lift arm intermediate its ends, and is adjustably connected to the pivot bracket at its opposite end by an eccentric pin, movable in an open slot in the swing arm to offset the roll axis as required and to accommodate the insertion of a feeler gage, to determine the direction of the resultant horizontal forces, as the eccentric pin is adjustably moved.

OFFSET CALENDER ROLLS BACKGROUND OF THE INVENTION In a sheet calenders having calender rolls stacked one above the other, with a pressure nip between each pair of rolls, alternate rolls in the stack are horizontally deflected in opposite directions, due to the driving forces on the rolls and the forces produced by sheet tension. This causes bar marking of the sheet, sheet edge pinching, quarter point wrinkling and hard centered reels as well as nonuniform roll wear.

It has been attempted to remedy these difficulties by the use of stiffer calender rolls, nip relieving, and by offsetting the calender rolls horizontally with respect to each other. Of these attempted remedies, horizontally offsetting the rolls has been the most satisfactory, but it has been difficult to properly offset the rolls since the rolls are only properly offset when the horizontal component of nip forces balances the combination of sheet tension and driving forces.

One way in which the offsetting has been attained has been to introduce shims between the calender support posts and the calender ann pivot brackets. This is a cut and try method, but does accomplish the desired results when the rolls are properly offset.

Another way in which the rolls have been offset has been to provide an eccentric pin and a mechanical operator for the pin, along with readout and strain gages on the calender roll support arms, so that the required offset may be determined when the strain gage shows no resultant horizontal force. One deficiency in this method of offsetting a calender roll, aside from the fact that the system is expensive and complicated, is that any one combination of offset is correct for only one specific sheet tension and nip pressure. A small change in nip pressure or sheet tension will produce a horizontal resultant force which is only a small fraction of the horizontal force which would have resulted if the rolls were not offset. Where an eccentric pivot for the lift arm is used to horizontally offset the axis, the pivot center is displaced vertically each time the roll center is offset and the nip relief devices must be reset each time the angle of the roll arms is changed by vertical displacement of the pivot center. This requires a continual adjustment of the nip relief devices, to counteract the changes in sheet tension or nip pressure, making it necessary to reset the nip relief devices each time a change in offset is made SUMMARY AND OBJECTS OF INVENTION By the structure of the present invention, I materially simplify the horizontal offsetting of calender rolls by so supporting the lift arms for the calender rolls that they will be maintained in a substantially horizontal plane between the roll centers and pivot centers, as the roll centers are offset horizontally, to stabilize for changing nip pressures and the resultant horizontal forces exerted on the rolls by the tension of the sheet, by mounting the lift arms for the calender rolls on swing arms pivoted to the pivot brackets for the calender rolls and by adjusting the swing arms to horizontally shift the roll pivots, by the use of an eccentric pin connected between the pivot brackets and swing arms, and by the provision of an opening along the region of connection of each eccentric pin to its swing arm to enable the direction of horizontal force to readily be determined by a feeler gage and the like.

It is, accordingly, a principal object of the present invention to provide a simplified mechanism for horizontally offsetting calender rolls with respect to each other which maintains the roll-supporting swing arm pivot in a substantially horizontal plane between the roll and swing arm pivot centers.

A further object of the invention is to provide a simple sup port mechanism for the lift arms of calender rolls, in which the lift arms are pivotally supported on horizontally adjustable swing arms, intermediate the ends of the swing arms, and eccentric adjustment means is provided for the swing arms, horizontally shifting the lift arm pivots in substantially horizontal planes between the roll and pivot centers.

Another object of the invention is to provide an improved form of mechanical horizontally adjustable means for offsetting calender rolls, arranged with a view toward utmost simplicity and economy in construction and operation and avoiding the necessity of providing complicated electronic equipment to determine proper offsetting of the rolls.

These and other objects of the invention will appear from. time to time as the following specification proceeds and with reference to the accompanying drawings wherein:

FIG. 1 is a fragmentary generally diagrammatic view in side elevation of a portion of a calender stack constructed in accordance with the principles of the present invention;

FIG. 2 is a plan view ofa calender roll support lift arm and pivot bracket, illustrating one form in which the calender roll axis may be offset horizontally in accordance with the principles of the present invention; and

FIG. 3 is a view in side elevation of the roll support lift arm shown in FIG. 2, showing the support for the lift ann on the calender pivot bracket.

DESCRIPTION OF PREFERRED EMBODIMENT OF THE INVENTION In the embodiment of the invention illustrated in the drawings, I have shown in FIG. I a fragment of a calender stack 10, comprising a base 11 forming a support for a pair of spaced upright posts 12, suitably connected in parallel spaced relation with respect to each other. The base 11 also forms a support for bearing supports 13 for a bottom or king roll 15, which may be driven by power in a conventional manner. Extending above thebottom roll 15 and supported on said bottom roll is a series of superposed calender rolls l6, l6, providing a series of pressure nips between said calender rolls and between the bottom calender roll I6 and the bottom roll 15, each roll 16 defining a calender nip with the roll immediately below it.

The bottom roll I5 serves as a finishing roll and may have a plated surface, plated with chrome or nickel, to provide a highly polished surface where the stack is used for a glossing treatment. The superposed rolls I6, I6 are driven by contact with a web W trained through the nips thereof and the nip between the lower rolls l6 and the bottom I5, although they may be positively driven under certain conditions.

The rolls l6, 16 are of a similar construction. Each roll is mounted at its opposite ends on the posts l2, 12 in a similar manner, so the mounting of one end of one roll and its horizontal offsetting means only, need herein be shown and described in detail.

Each roll 16 is journaled at its opposite ends in antifrietion bearings (not shown) mounted in bearing housings 17,.17 carried on the outer ends of lift arms 19, 19 in a conventional manner. The lift arms l9, 19 extend rearwardly of the bearing housing l7, 17 along the inner sides of the posts l2, l2 and are transversely pivoted thereto on pivot brackets 20, in accordance with the principles of the present invention, as will hereinafter more clearly appear as this specification proceeds.

The lift arms 19 extend rearwardly of the posts 12 and each has an upper bearing pad 21 engaged by a load-relieving fluid pressure operated diaphragm or air spring 23. The air spring 23 is shown as mounted on and abutting the undersurface of a horizontal arm 24 of an angle bracket 25, shown as being mounted on the rear side of the post I2, with the horizontal arm 24 extending rearwardly therefrom. The admission of fluid under pressure to the diaphragms 23 will thus pivot the lift arms I) and the bearing housing I7 about the axes of lift arm pivots 27, to relieve a part of the load between the nips of the calender rolls I6and the bottom roll I5 and a part of the weight of the bearing housings 17, the bearings carried by said housings and the overhanging weight of the lift arms I9, in a conventional manner. Suitable valve means (not shown) may be provided to admit air to the diaphragms 23 independently of each other, as selected by the operator of the machine.

A suitable lifting means (not shown) may also be provided to lift the calender rolls out of engagement with each other at the termination of a calendering operation. Said lifting means may be of any conventional form and is no part of the present invention so need not herein be shown or described.

Laterally spaced loading rolls 29 may be spaced along the top calender roll 16 for loading the top roll of the calender stack. The loading rolls 29 may load the top roll of the calender stack by fluid pressure operated cylinders 30, pivoted to brackets 31 extending rearwardly of the post 12, on pivot pins 32. The fluid pressure operated cylinders and pistons may lift the loading rolls 29 above the top calender roll, and are movable to engage and load the top calender roll by operation of the fluid pressure operated cylinders and pistons 30, in a manner which is no part of the present invention so need not herein be shown or described further. it should here be understood that the present invention is not dependent upon the loading rolls and that the loading rolls need only be used where required by specific calendering conditions.

Referring now in particular to the means supporting the lift arm pivots 27 and lift arms 19, and offsetting the pivotal axis of the associated calender roll 16 in a substantially horizontal plane extending along the calender roll axis and lift arm pivots 27 each pivot bracket 20 is bolted or otherwise secured to the front face of a calender post 12 and has a pair of laterally spaced pivot bosses 33 extending forwardly therefrom adjacent the lower end thereof. The spaced pivot bosses 33 form a mounting for opposite ends of a pivot pin 35, forming a pivotal support for a swing arm 36, extending between the pivot bosses 33 and upwardly therefrom.

The swing arm 36 extends through a central open portion 37 formed in the lift arm 19 and forms a support for said lift arm on the lift arm pivot 27. The lift arm pivot 27 is shown as extending through said swing arm and as being suitably mounted in opposite sides of the open portion 37 of said lift arm 19, as by concentric bearings 39.

The swing arm 36 extends upwardly between a pair of paral lel spaced bosses 40 extending forwardly of the upper end portion of the pivot bracket 20. The bosses 40 form a mounting means for an eccentric pin 41. The eccentric pin 41 has opposite end portions 42 mounted in the spaced bosses 40 for rotation about an axis extending eccentrically of the center said eccentric pin. Said eccentric pin 41 extends along an upwardly opening slot 43 in the swing arm 36. The eccentric pin 41 may be adjustably moved with respect to bosses 40 about an axis eccentric of its center and held in position in said bosses by a suitable adjusting arm 45 extending upwardly therefrom and secured to an end portion 42 thereof. The arm 45 may be adjusted by a screw mechanism 47 diagrammatically shown in FIG. 1, and no part of the present invention except insofar as it forms a means for rotatably adjusting the eccentric pin 41 to shift the lift arm pivot 27 and roll axis laterally in a generally horizontal plane and holding the eccentric pin 41 in position. The adjusting mechanism, however, may be of any well-known form, so need not herein be shown or described further.

The eccentric pin 41 shown herein, affords horizontal adjustment of the lift arm pivot 27 and roll axis, of plus or minus five-eighth inches in either a right-hand or left-hand direction. The adjustment, of course, may be varied by varying the eccentricity of the eccentric pin as we as the size thereof.

The slot 43 within which the eccentric pin extends opens upwardly to provide free access from the top of the pivot bracket between the bosses 40, for a feeler gauge diagrammatically illustrated and designated by reference character 48. The feeler gauge 48 may readily be inserted between the eccentric pin 41 and the slot 43 to determine the direction of the resultant horizontal force on the calender roll. The ideal location of the lift arm pivot 27 and the ideal roll offset is at a location where the horizontal resultant force changes direction as indicated by the shift of clearance between the pin 41 and slot 43, from one side ofthe other of the slot.

indicators (not shown) may be attached to the calender posts or pivot brackets, to permit the returning of the lift arm pivot 27 to a given setting or to check alignment between the two ends of the roll. These indicators may be of a conventional form and are no part of the present invention so need not herein be shown or described.

It may be seen from the foregoing that a simplified mounting for the lift arm of the calender rolls of a calender stack has been provided, in which horizontal adjustment of the lift arms along the calender rolls axes and lift arm pivots is attained by mounting the lift arms on pivot brackets for the calender stack, on swing arms pivotally movable at their lower ends about axes extending transversely of the lift arms, and retained in position and horizontally adjustably moved at their upper ends by eccentric adjustment pins rotatably carried in the pivot brackets for the lift arms, and adjusting the lift arms horizontally in a substantially straight line direction, and thus making it possible to offset the calender rolls horizontally without changing the nip-relieving pressures, each time the calender rolls are offset.

It may further be seen that the ideal location of the lift arm pivot may readily be determined by the simple use of a feeler gauge indicating the horizontal resultant force changes in direction, by the shift of clearance between the eccentric pin and the slot in the swing arm through which the eccentric pin extends, without the necessity of resorting to complicated electronic equipment.

While I have herein shown and described one form in which the invention may be embodied, it may readily be understood that various variations and modifications of the invention may be attained without departing from the spirit and scope of the novel concepts thereof.

I claim as my invention:

1. In a calender stack:

a bottom roll,

a series of superposed calender rolls supported on said bottom roll and forming a pressure nip with said bottom roll and pressure nips between said superposed rolls,

the combination with a frame forming a mounting for said bottom roll and having a pair of calender posts extending upwardly therefrom,

pivot brackets for supporting said calender rolls on said posts,

a lift arm pivotally supported on each pivot bracket intermediate its ends,

a calender roll bearing on the end of each lift arm forming a bearing for an end ofa calender roll,

and individual means supporting each lift arm on an associated pivot bracket and horizontally adjustable to shift the calender roll axis of rotation and lift arm pivot in a generally horizontal plane, to horizontally offset the calender rolls with respect to each other, comprising: a swing arm pivoted to each pivot bracket at one end, a pivot pin pivotally mounting said lift arm on said swing arm intermediate the ends of said swing arm, and adjustment means connecting said pivot bracket with the opposite end of said swing arm from the swing arm pivot, for horizontally shifting said lift arm pivot in accordance with the conditions required to cancel the horizontal force produced by the driving and sheet tension forces.

2. A calender stack in accordance with claim 1, wherein the adjustment means is an eccentric adjustment pin mounted in said pivot bracket for rotatable movement with respect thereto about an axis eccentric of its center and having slidable adjustable engagement with said swing arm.

3. A calender stack in accordance with claim 1,

wherein said swing arm has an open slot therein slidably engaged by said eccentric pin, and

wherein said open slot affords access for a feeler gauge to determine the direction of the horizontal resultant force on the calender roll.

4. A calender stack in accordance with claim I,

wherein the pivot bracket has at least one boss extending from its lower end toward the calender roll,

wherein a pivot pin pivotally mounts said swing arm on said boss at the lower end of said swing arm,

wherein said lift arm has anopening therein, through which said swing arm extends,

wherein the pivot pin pivotally mounting said lift arm on said swing arm extends through said opening and through the center of said swing arm,

wherein said pivot bracket has a boss extending from the upper end thereof toward said calender roll, and

wherein the adjustment means is mounted in said last mentioned boss for rotatable movement with respect thereto about an axis eccentric of its center and has slidable engagement with the upper end of said swing arm for shifting said pivot pin for said lift arm horizontally to offset said pivot pin and the calender roll center in a generally horizontal plane.

5. A calender stack in accordance with claim 4,

wherein the adjustment means comprises an eccentric pin rotatably mounted in said boss.

6. A calender stack in accordance with claim 4,

wherein the adjustment means comprises an eccentric pin rotatably mounted in said upper boss, and

wherein said swing arm has an upwardly opening slot therein slidably engaged by said eccentric pin and affording a means for access of a fe'eler gauge to determine the direction of the horizontal resultant forces on the calender roll.

7. A horizontally shiftable mounting means for each end of a calender roll and the like comprising,

a stationary pivot bracket,

a lift arm,

a calender roll bearing on one end of said lift arm,

a swing arm pivoted to said bracket at one end,

a pivot pin pivotally mounting said lift arm on said swing arm intermediate the ends of said swing arm, and

eccentric adjustment means adjustably mounted in said pivot bracket and having adjustable connection with the opposite end of said swing arm from the swing arm pivot,

for selectively shifting said lift arm pivot horizontally in accordance with the conditions required to cancel the horizontal forces produced by the driving and sheet tension forces.

8. A calender roll mounting in accordance with claim 7,

wherein said eccentric adjustment means is an eccentric wherein said swing arm has a slot therein opening to the end thereof opposite from said swing arm pivot and slidably engaged by said eccentric pin, and

wherein said open slot affords access for gauge means to determine the direction of the horizontal resultant forces on the calender roll.

9. A calender roll mounting in accordance with claim 7 wherein the pivot bracket has at least one boss extending from its lower end towards the calender roll,

wherein a pivot pin mounts said swing arm on said boss at the lower end of said swing arm,

wherein the lift arm has an opening therein through which the swing arm extends,

wherein the pivot pin pivotally mounting said lift arm on said swing arm extends through said opening and through the center ofsaid swing arm,

wherein said pivot bracket has a boss extending from the upper end thereof towards the calender roll, and

wherein the eccentric adjustment means is an eccentric pin mounted in said boss for adjustable movement about an axis eccentric of its center, and has slidable engagement with the upper end of said swing arm for shifting said pivot pin for said lift arm horizontally to offset said pivot pin and the calender roll center in a generally horizontal plane.

10. A calender roll mounting in accordance with claim 9 wherein the swing arm has an upwardly opening slot therein slidably engaged by said eccentric pin and affording a means for access of a gua e means to determine the direction of the horizonta resultant forces on the calender roll. 

1. In a calender stack: a bottom roll, a series of superposed calender rolls supported on said bottom roll and forming a pressure nip with said bottom roll and pressure nips between said superposed rolls, the combination with a frame forming a mounting for said bottom roll and having a pair of calender posts extending upwardly therefrom, pivot brackets for supporting said calender rolls on said posts, a lift arm pivotally supported on each pivot bracket intermediate its ends, a calender roll bearing on the end of each lift arm forming a bearing for an end of a calender roll, and individual means supporting each lift arm on an associated pivot bracket and horizontally adjustable to shift the calender roll axis of rotation and lift arm pivot in a generally horizontal plane, to horizontally offset the calender rolls with respect to each other, comprising: a swing arm pivoted to each pivot bracket at one end, a pivot pin pivotally mounting said lift arm on said swing arm intermediate the ends of said swing arm, and adjustment means connecting said pivot bracket with the opposite end of said swing arm from the swing arm pivot, for horizontally shifting said lift arm pivot in accordance with the conditions required to cancel the horizontal force produced by the driving and sheet tension forces.
 2. A calender stack in accordance with claim 1, wherein the adjustment means is an eccentric adjustment pin mounted in said pivot bracket for rotatable movement with respect thereto about an axis eccentric of its center and having slidable adjustable engagement with said swing arm.
 3. A calender stack in accordance with claim 1, wherein said swing arm has an open slot therein slidably engaged by said eccentric pin, and wherein said open slot affords access for a feeler gauge to determine the direction of the horizontal resultant force on the calender roll.
 4. A calender stack in accordance with claim 1, wherein the pivot bracket has at least one boss extending from its lower end toward the calender roll, wherein a pivot pin pivotally mounts said swing arm on said boss at the lower end of said swing arm, wherein said lift arm has an opening therein, through which said swing arm extends, wherein the pivot pin pivotally mounting said lift arm on said swing arm extends through said opening and through the center of said swing arm, wherein said pivot bracket has a boss extending from the upper end thereof toward said calender roll, and wherein the adjustment means is mounted in said last mentioned boss for rotatable movement with respect thereto about an axis eccentric of its center and has slidable engagement with the upper end of said swing arm for shifting said pivot pin for said lift arm horizontally to offset said pivot pin and the calender roll center in a generally horizontal plane.
 5. A calender stack in accordance with claim 4, wherein the adjustment means comprises an eccentric pin rotatably mounted in said boss.
 6. A calender stack in accordance with claim 4, wherein the adjustment means comprises an eccentric pin rotatably mounted in said upper boss, and wherein said swing arm has an upwardly opening slot therein slidably engaged by said eccentric pin and affording a means for access of a feeler gauge to determine the direction of the horizontal resultant forces on the calender roll.
 7. A horizontally shiftable mounting means for each end of a calender roll and the like comprising, a stationary pivot bracket, a lift arm, a calender roll bearing on one end of said lift arm, a swing arm pivoted to said bracket at one end, a pivot pin pivotally mounting said lift arm on said swing arm intermediate the ends of said swing arm, and eccentric adjustment means adjustably mounted in said pivot bracket and having adjustable connection with the opposite end of said swing arm from the swing arm pivot, for selectively shifting said lift arm pivot horizontally in accordance with the conditions required to cancel the horizontal forces produced by the driving and sheet tension forces.
 8. A calender roll mounting in accordance with claim 7, wherein said eccentric adjustment meaNs is an eccentric pin, wherein said swing arm has a slot therein opening to the end thereof opposite from said swing arm pivot and slidably engaged by said eccentric pin, and wherein said open slot affords access for gauge means to determine the direction of the horizontal resultant forces on the calender roll.
 9. A calender roll mounting in accordance with claim 7 wherein the pivot bracket has at least one boss extending from its lower end towards the calender roll, wherein a pivot pin mounts said swing arm on said boss at the lower end of said swing arm, wherein the lift arm has an opening therein through which the swing arm extends, wherein the pivot pin pivotally mounting said lift arm on said swing arm extends through said opening and through the center of said swing arm, wherein said pivot bracket has a boss extending from the upper end thereof towards the calender roll, and wherein the eccentric adjustment means is an eccentric pin mounted in said boss for adjustable movement about an axis eccentric of its center, and has slidable engagement with the upper end of said swing arm for shifting said pivot pin for said lift arm horizontally to offset said pivot pin and the calender roll center in a generally horizontal plane.
 10. A calender roll mounting in accordance with claim 9 wherein the swing arm has an upwardly opening slot therein slidably engaged by said eccentric pin and affording a means for access of a guage means to determine the direction of the horizontal resultant forces on the calender roll. 